General Redirection Methods

In this section, we will delve deeper into the various redirection
methods that are commonly used for both servers and proxies. These
techniques can be used to redirect traffic to a different (presumably
more optimal) server or to vector traffic through a proxy.
Specifically, we'll cover HTTP redirection, DNS
redirection, anycast addressing, IP MAC forwarding, and IP address
forwarding.

HTTP Redirection

Web servers can send short redirect
messages back to clients, telling them to try someplace else. Some
web sites use HTTP redirection as a simple form of load balancing;
the server that handles the redirect (the redirecting server) finds
the least-loaded content server available and redirects the browser
to that server. For widely distributed web sites, determining the
"best" available server gets more
complicated, taking into account not only the
servers' load but the Internet distance between the
browser and the server. One advantage of HTTP redirection over some
other forms of redirection is that the redirecting server knows the
client's IP address; in theory, it may be able to
make a more informed choice.